1. Technical Field
The present disclosure relates to an electrical fuse programming control circuit for a semiconductor device and, more particularly, to an electrical fuse programming control circuit that can program a fuse by using an end fuse block, even when an illegal program command is provided as an input.
2. Description of the Related Art
In general, a laser fuse is programmed by directly rupturing a fuse that is selected by an external physical force (laser beam). Conversely, an electrical fuse is programmed by transmitting an electrical stress to the selected electrical fuse in response to an externally-inputted program command, and thereby rupturing the electrical fuse.
When the electrical fuse is used for repair, a desired fuse block is selected from among a plurality of fuse blocks according to specific information (e.g., address). An electrical stress is then transmitted to the selected fuse block to program the electrical fuse. More specifically, when information stored in fuse blocks that are programmed in a normal mode is the same as an externally-inputted address, the externally-inputted address does not access a normal memory cell array, but instead enables a control signal to access a repair memory cell as the repair address.
FIG. 1 is an exemplary block diagram that depicts a conventional electrical fuse programming control circuit for repair. In this example, the electrical fuse is formed as an anti fuse. The electrical fuse programming control circuit for repair includes a plurality of fuse blocks FB1˜FBn having a plurality of anti fuses (not shown). In addition, the electrical fuse programming control circuit for repair includes a control signal generating unit 1 adapted to enable a control signal CON when information stored in the fuse blocks FB1˜FBn that are programmed in the normal mode is the same as an externally-inputted address ADD. The individual fuse blocks FB1˜FBn are selected in response to the externally-inputted repair addresses RADD<1:n>. The selected fuse blocks enter into an electrical fuse programming mode, and are thereby programmed in response to a fuse cutting signal FCS.
When the electrical fuse is used for voltage trimming, a desired fuse block is selected from among the plurality of fuse blocks in response to a control signal. The control signal is adapted to select specific information such as a specific level. An electrical stress is then transmitted to the selected fuse block to program the electrical fuse. Accordingly, a select signal for selecting the specific level is enabled based on the information stored in the fuse blocks.
FIG. 2 is an exemplary block diagram that depicts a conventional electrical fuse programming control circuit for voltage level trimming. The electrical fuse programming control circuit for voltage level trimming includes a plurality of fuse blocks FB1˜FBn having a plurality of anti fuses (not shown). The electrical fuse programming control circuit for voltage level trimming also includes a decoding unit 2 adapted to decode the information stored in the anti fuses of the fuse blocks FB1˜FBn, and generate a select signal SEL for selecting a desired voltage level. The individual fuse blocks FB1˜FBn are selected in response to the voltage control signals CTRL1˜CTRLn. When the fuse cutting signal FCS is enabled, the selected fuse block enters into the electrical fuse programming mode to be programmed.
When the electrical fuse is used for mode selection, a desired fuse block is selected in response to a control signal. The control signal is adapted to select specific information such as specific mode. An electrical stress is then transmitted to the selected fuse block to program the electrical fuse. Accordingly, a mode select signal for selecting the specific mode is enabled based on the information stored in the fuse blocks.
However, when a device utilizing the electrical fuse is used in a system, if an illegal program command is provided to the programmed fuses as an input, the device is configured based on the illegal information (i.e., address, level, mode, etc.). As a result, an illegal reprogramming operation is performed.